US4226122A - Apparatus for recording echo pulses - Google Patents

Apparatus for recording echo pulses Download PDF

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Publication number
US4226122A
US4226122A US05/919,602 US91960278A US4226122A US 4226122 A US4226122 A US 4226122A US 91960278 A US91960278 A US 91960278A US 4226122 A US4226122 A US 4226122A
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United States
Prior art keywords
echo
projection
signals
recording
amplitude
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Expired - Lifetime
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US05/919,602
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English (en)
Inventor
Svend A. Lund
Sven E. Iversen
Carl E. T. Petersen
Erik T. Bogen
Jorgen Dam
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Akademiet for de Tekniske Videnskaber
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Akademiet for de Tekniske Videnskaber
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/06—Visualisation of the interior, e.g. acoustic microscopy
    • G01N29/0609—Display arrangements, e.g. colour displays
    • G01N29/0618—Display arrangements, e.g. colour displays synchronised with scanning, e.g. in real-time
    • G01N29/0636—Display arrangements, e.g. colour displays synchronised with scanning, e.g. in real-time with permanent recording
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/06—Visualisation of the interior, e.g. acoustic microscopy
    • G01N29/0609—Display arrangements, e.g. colour displays
    • G01N29/0618—Display arrangements, e.g. colour displays synchronised with scanning, e.g. in real-time
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/02—Indexing codes associated with the analysed material
    • G01N2291/028—Material parameters
    • G01N2291/02854—Length, thickness

Definitions

  • the present invention relates to an apparatus for recording echo pulses from inhomogeneities in otherwise homogeneous objects having a plane or slightly curved surface, by ultrasonic inspection according to the pulse echo method using a least one angle probe which can be moved freely in a two-dimensional scanning movement over the surface of the object, comprising position signal producing means for producing signals containing information on the position of the sound emission point of the probe and the direction of the projection of the sound beam on the surface of the object, co-ordinate signal producing means for producing, on receipt of echo pulses, on the basis of the position signals and the transit time of the ultrasonic pulses, signals containing information on the spatial co-ordinates of the reflecting points of the object causing the echo pulses, and a memory for storing or recording the data produced by the inspection.
  • the present invention has for its object to provide a simplification of the equipment used, and a reduction of the time necessary for the reproduction of data, through a reduction of the amount of data stored.
  • the memory provided with at least one storage position for the amplitude of the echo signal from each reflecting point within the inspected area of the object, and by having the apparatus arranged to bring about, on receipt of each echo pulse, the recording of its amplitude in at least one storage position determined by the appurtenant co-ordinate signals, but only if an echo amplitude higher than the last incoming amplitude has not already been recorded in the storage position in question.
  • the recording is position-based which implies in itself a substantial simplification, because in the known time-based recording, a recording of all echoes from each individual reflecting point takes place. The fact that only the highest echo signal from each reflecting point is recorded represents a substantial further simplification.
  • the memory can have a storage position for each possible reflecting point within the inspected area of the object, and at each storage position means can be provided for recording the echo amplitude.
  • the memory contains all the data necessary for reproducing the data produced by the ultrasonic inspection.
  • the apparatus may contain display means for producing, from the recorded amplitude data and the appurtenant storage positions, pictures of the reflecting points corresponding to projection pictures on the surface of the object and on planes perpendicular thereto.
  • the memory may have, according to the invention, for each desired projection picture, a number of storage positions corresponding to the projections of the possible reflecting points on the appurtenant projection plane, means being provided at each storage position for recording the highest occurring echo amplitude. In this case a further substantial reduction of the recorded data amount is obtained. This is due to the fact that only the largest of the echo signals originating from a reflecting point lying on a line perpendicular to the projection plane in question is recorded.
  • the apparatus according to the invention can be arranged for displaying echo signals of an amplitude lying above a given level with a first display characteristic and echo signals of an amplitude lying below said level with another display characteristic; the latter characteristic including the possibility of no display. This makes the interpretation of the displayed pictures much simpler.
  • the apparatus according to the invention can be arranged for displaying the echo signals with more than two different display characteristics, by classifying the echo signals according to several levels.
  • the levels can be adjustable.
  • the different display characteristics can consist of different shades of gray.
  • FIG. 1 shows an ultrasonic probe with appurtenant position signal producing means disposed on an object to be inspected
  • FIGS. 2 and 3 are sections through the object in two directions perpendicular to one another
  • FIG. 4 is a block diagram of an embodiment of the apparatus according to the invention.
  • FIG. 5a and 5b show schematically a memory
  • FIG. 6 is an example of a screen picture produced with an apparatus according to the invention.
  • FIG. 7 is an example of the insertion of a reference curve in a part of a screen picture as shown in FIG. 6.
  • FIG. 1 shows an ultrasonic probe 1 as shown in FIG. 2 emits an ultrasonic beam 2, into an object 3 containing a weld 4 to be inspected.
  • the beam 2 forms a constant angle with the surface of the object.
  • the arrow 5 in FIG. 1 indicates the projection of the ultrasonic beam on the surface of the object.
  • the ultrasonic probe 1 is, through a lever device provided with two arms 6 and 7 which are pivotally connected with each other, coupled to a block 8 which during the test is secured to the object, e.g. by gravitation or by means of a magnet, and thus constitutes a fixed point.
  • the arm 7 is pivotally connected with a vertical arm 9 which is rotatable in the block 8.
  • the arm 6 is pivotally connected with a vertical arm 10 about which the ultrasonic probe 1 can rotate.
  • the ultrasonic probe 1 can be moved freely in a two-dimensional movement over the surface of the object, while being continually coupled to the stationary block 8 via the lever device.
  • the position of the ultrasonic probe 1 and thereby the sound emitting point, which preferably lies directly under the arm 10, is determined by two angles, viz. the angle position ⁇ of the arm 9 in relation to the block 8, which determines the direction to the ultrasonic probe, and the angle ⁇ between the arms 7 and 9, which determines the distance to the ultrasonic probe.
  • the direction of the projection 5 of the ultrasonic beam is determined by the angle ⁇ in connection with the angle position ⁇ of the ultrasonic probe in relation to the arm 10.
  • the ultrasonic beam 2 from the probe 1 is reflected up and down between the bottom and the top of the object, and as it will appear from FIG. 2, it is the part of the beam reflected once from the bottom which is used for testing the weld 4. It is, however, also possible to utilize other parts of the beam path for the test.
  • an inhomogeneity 11 is indicated in the form of a weld flaw which will send a strong ultrasonic echo back to the ultrasonic probe 1.
  • FIG. 4 shows the ultrasonic probe 1 electrically connected to a conventional ultrasonic apparatus 12 adapted to produce electric pulses for actuating the ultrasonic probe 1, so that it emits ultrasonic pulses into the object, and for treating the electric pulses produced when the reflected ultrasonic energy reaching the ultrasonic probe 1 causes the production of electrical pulses in said probe.
  • a control device 13 From the ultrasonic apparatus 12, data on the transit time of the ultrasonic pulses and the echo amplitudes are transmitted to a control device 13. Information on the angles ⁇ , ⁇ and ⁇ is furthermore transmitted to the control device 13 from the angle transducers incorporated in the lever system. On the basis of the data received, the control device 13 is in a position to determine the co-ordinates of the reflecting points.
  • the result of the manual or automatic scanning of the weld by means of the ultrasonic probe 1 can be displayed on a storage screen in the display device 14.
  • the data produced by the control device 13 is further transmitted to a microcomputer 15 containing a memory 16 and connected to a magnetic tape unit 17 and a screen terminal 18.
  • related values of the echo amplitude and the co-ordinates of the reflecting point in question are determined, and these values are recorded in the memory 16.
  • Said memory can, for instance, be arranged as schematically indicated in FIG. 5a and 5b.
  • the co-ordinates X, Y, Z of a reflecting point are drawn along three directions perpendicular to one another within the cube, and in the storage position thus arrived at, the echo amplitude A is recorded. This requires the provision at each storage position of a storage element which is able to record as many different amplitude values as it is desired to display.
  • the computer 15 is arranged so that, for each individual storage position, only the largest of the amplitudes produced during the inspection from the corresponding reflecting point is recorded, the arrangement of the memory in question is nevertheless comparatively complicated. Since what is desired to be displayed by means of the recorded data will normally be projection pictures on projection surfaces which are perpendiculer to one another, the simpler construction of the memory indicated in FIG. 5b can be used. This construction uses two separate areas 17 and 18 of the memory for recording the data necessary to the production of projection pictures on a plane parallel to the surface of the object and a plane perpendicular thereto, which is parallel to the weld, respectively.
  • the faces of the two areas 17 and 18 appearing foremost in the drawing correspond geometrically to the two projection planes and, at any point of these faces, the value of the greatest echo received from all the reflecting points situated on a line perpendicular to the projection plane in the corresponding point is recorded at right angles to the face.
  • the contents of the memory 16 can be transferred to a magnetic tape in the magnetic tape unit 17 and can again be returned from the magnetic tape to the memory 16.
  • a magnetic tape instead of a magnetic tape, another recording medium can be used.
  • the lower band marked "amplitude" indicates the largest amplitude from the reflecting point whose echo pulse is indicated in the two above-situated bands vertically above the amplitude indication in question.
  • the key-board and the screen terminal 18 it is possible to communicate with the computer 15.
  • the data necessary to the calculation of the co-ordinates of the reflecting points can be introduced by means of the key-board. It may, for instance, be the thickness of the object, the angle of the ultrasonic beam with the surface of the object or the velocity of sound in the material constituting the object.
  • the key-board it is furthermore possible to insert a reference level 19 in the display, cf. FIG. 6.
  • the insertion of the reference level results in the part of the amplitude of the echo pulses which is greater than the reference level being shown with another display characteristic--here a darker gray shade--than the part of the echo amplitude lying below the reference level.
  • the insertion of the reference line results in only the echoes whose amplitude is higher than the reference level being displayed. It is possible to arrange the display so that the echo amplitudes below the reference level are not shown at all.
  • the reference level 19 can suitably be placed at that value, and the two upper bands will therefore only show the echoes originating from flaws which are not tolerable.
  • FIG. 4 the screen terminal 18 is shown connected to a copy unit 20 whereby hard copies of the screen picture can be produced.
  • the apparatus can be arranged so that in the visualization of the echo amplitudes, instead of a reference level, as shown in FIG. 6, a reference curve 21, as shown in FIG. 7, is inserted, which in all essentials corresponds to the envelope of the background echoes. This makes it substantially easier to distinguish the flaw echoes from the background echoes, than if use was made of a fixed level lying above the amplitudes of the background echoes.

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  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
US05/919,602 1977-07-01 1978-06-27 Apparatus for recording echo pulses Expired - Lifetime US4226122A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DK2961/77 1977-07-01
DK296177AA DK139597B (da) 1977-07-01 1977-07-01 Apparat til registrering af ekkoimpulser ved ultralydundersøgelser.

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US4226122A true US4226122A (en) 1980-10-07

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US (1) US4226122A (fr)
JP (1) JPS5414292A (fr)
BR (1) BR7804212A (fr)
DE (1) DE2828376A1 (fr)
DK (1) DK139597B (fr)
FR (1) FR2396296A1 (fr)
GB (1) GB2000591B (fr)
IT (1) IT1103446B (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4441369A (en) * 1982-09-30 1984-04-10 General Electric Company Ultrasonic detection of extended flaws
US4799168A (en) * 1985-12-31 1989-01-17 The Boeing Company Data recording apparatus for an ultrasonic inspection system
US4836026A (en) * 1984-06-01 1989-06-06 Science Applications International Corporation Ultrasonic imaging system
US4908774A (en) * 1986-05-05 1990-03-13 Akademiet For De Tekniske Videnskaber System for ultrasonic examination
US4911014A (en) * 1988-07-22 1990-03-27 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method of analyzing and evaluating the results of an ultrasonic examination
US5111696A (en) * 1989-01-24 1992-05-12 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method of visualizing reflection characteristic in ultrasonic examination
US5383365A (en) * 1992-09-17 1995-01-24 The Babcock & Wilcox Company Crack orientation determination and detection using horizontally polarized shear waves
US20030130825A1 (en) * 2002-01-10 2003-07-10 Siemens Aktiengesellschaft Averaging trace function with indexing by a process signal
US20060137451A1 (en) * 2004-12-27 2006-06-29 Dewangan Sandeep K Method and system for inspecting flaws using ultrasound scan data
US10187504B1 (en) * 2016-09-23 2019-01-22 Apple Inc. Echo control based on state of a device

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JPS5990045A (ja) * 1982-11-15 1984-05-24 Power Reactor & Nuclear Fuel Dev Corp 手動式超音波探傷装置
DE3376586D1 (en) * 1982-12-03 1988-06-16 Degussa Apparatus for testing the purity of noble metal shaped bodies
FR2570502B1 (fr) * 1984-09-14 1988-01-15 Dassault Avions Installation pour le controle ultrasonore de pieces, et dispositif pour balayer une surface de la piece a controler
DE3525376A1 (de) * 1985-07-16 1987-01-29 Nukem Gmbh Verfahren und vorrichtung zur zerstoerungsfreien pruefung von ferromagnetischen koerpern mit oberflaechenabschnitten, die an kanten und/oder ecken aneinandergrenzen
AT391210B (de) * 1985-10-03 1990-09-10 Voest Alpine Ag Verfahren zur bestimmung der art von punktfoermigen und laengserstreckten einzelfehlern in werkstuecken mittels ultraschall
DE3908648A1 (de) * 1989-03-16 1990-09-20 Dornier Medizintechnik Darstellung von ultraschall-bildern
JPH0345533U (fr) * 1989-09-13 1991-04-26
JP2005156305A (ja) * 2003-11-25 2005-06-16 Daido Steel Co Ltd 内部欠陥の評価方法
JP4559931B2 (ja) * 2005-08-12 2010-10-13 日立Ｇｅニュークリア・エナジー株式会社 超音波探傷方法

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US3482434A (en) * 1966-02-23 1969-12-09 Automation Ind Inc Ultrasonic nondestructive tester including means for separating electrical noise from the electrical signals
US3872715A (en) * 1974-02-13 1975-03-25 Krautkramer Branson Ultrasonic pulse-echo gate circuit
US3939697A (en) * 1972-08-28 1976-02-24 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method and apparatus for ultrasonic examination
US3962909A (en) * 1973-09-05 1976-06-15 svejsecentralen Akademiet for De Tekniske Videnskaber Method and apparatus for ultrasonic examination
US4030344A (en) * 1975-05-12 1977-06-21 Akademiet For De Tekniske Videnskaber, Svejsecentralen Apparatus for recording an ultrasonic sectional view
US4058001A (en) * 1976-08-02 1977-11-15 G. D. Searle & Co. Ultrasound imaging system with improved scan conversion
DE2636401A1 (de) * 1976-08-11 1978-02-16 Mannesmann Ag Verfahren zur automatischen erkennung von ultraschallanzeigenstellen bei der zerstoerungsfreien pruefung metallischer werkstuecke

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DK118105B (da) * 1967-01-13 1970-07-06 Akad Tekn Videnskaber Fremgangsmåde til registrering, gengivelse og analysering af billedinformation ved ultralyd-snitbilledundersøgelser samt anlæg til udøvelse af fremgangsmåden.
US3673860A (en) * 1969-11-10 1972-07-04 Magnaflux Corp Non-destructive testing system having pattern recognition means
US3857052A (en) * 1972-04-28 1974-12-24 Rockwell International Corp Inspection and analysis system
AT346109B (de) * 1973-05-25 1978-10-25 Kretztechnik Gmbh Verfahren zum speichern und auswerten von aus untersuchungen bzw. untersuchungsschritten mit ultraschall erhaltenen informationen
US3864661A (en) * 1973-09-10 1975-02-04 Rohe & 0 Scient Corp Ultrascope
JPS5330024B2 (fr) * 1974-01-28 1978-08-24
JPH02108872A (ja) * 1988-10-19 1990-04-20 Nippon Denso Co Ltd 可変容量圧縮装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3482434A (en) * 1966-02-23 1969-12-09 Automation Ind Inc Ultrasonic nondestructive tester including means for separating electrical noise from the electrical signals
US3939697A (en) * 1972-08-28 1976-02-24 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method and apparatus for ultrasonic examination
US3962909A (en) * 1973-09-05 1976-06-15 svejsecentralen Akademiet for De Tekniske Videnskaber Method and apparatus for ultrasonic examination
US3872715A (en) * 1974-02-13 1975-03-25 Krautkramer Branson Ultrasonic pulse-echo gate circuit
US4030344A (en) * 1975-05-12 1977-06-21 Akademiet For De Tekniske Videnskaber, Svejsecentralen Apparatus for recording an ultrasonic sectional view
US4058001A (en) * 1976-08-02 1977-11-15 G. D. Searle & Co. Ultrasound imaging system with improved scan conversion
DE2636401A1 (de) * 1976-08-11 1978-02-16 Mannesmann Ag Verfahren zur automatischen erkennung von ultraschallanzeigenstellen bei der zerstoerungsfreien pruefung metallischer werkstuecke

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4441369A (en) * 1982-09-30 1984-04-10 General Electric Company Ultrasonic detection of extended flaws
US4836026A (en) * 1984-06-01 1989-06-06 Science Applications International Corporation Ultrasonic imaging system
US4799168A (en) * 1985-12-31 1989-01-17 The Boeing Company Data recording apparatus for an ultrasonic inspection system
US4908774A (en) * 1986-05-05 1990-03-13 Akademiet For De Tekniske Videnskaber System for ultrasonic examination
US4911014A (en) * 1988-07-22 1990-03-27 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method of analyzing and evaluating the results of an ultrasonic examination
US5111696A (en) * 1989-01-24 1992-05-12 Akademiet For De Tekniske Videnskaber, Svejsecentralen Method of visualizing reflection characteristic in ultrasonic examination
US5383365A (en) * 1992-09-17 1995-01-24 The Babcock & Wilcox Company Crack orientation determination and detection using horizontally polarized shear waves
US20030130825A1 (en) * 2002-01-10 2003-07-10 Siemens Aktiengesellschaft Averaging trace function with indexing by a process signal
DE10200682A1 (de) * 2002-01-10 2003-07-31 Siemens Ag Mittelwertbildende Trace-Funktion mit Indizierung durch ein Prozesssignal
DE10200682B4 (de) * 2002-01-10 2005-11-24 Siemens Ag Mittelwertbildende Trace-Funktion mit Indizierung durch ein Prozesssignal
US7401005B2 (en) 2002-01-10 2008-07-15 Siemens Aktiengesellschaft Averaging trace function with indexing by a process signal
US20060137451A1 (en) * 2004-12-27 2006-06-29 Dewangan Sandeep K Method and system for inspecting flaws using ultrasound scan data
US7234355B2 (en) * 2004-12-27 2007-06-26 General Electric Company Method and system for inspecting flaws using ultrasound scan data
US10187504B1 (en) * 2016-09-23 2019-01-22 Apple Inc. Echo control based on state of a device

Also Published As

Publication number Publication date
IT1103446B (it) 1985-10-14
DE2828376A1 (de) 1979-01-11
IT7809515A0 (it) 1978-06-30
DE2828376C2 (fr) 1987-09-17
GB2000591B (en) 1982-08-04
DK139597B (da) 1979-03-12
JPS5414292A (en) 1979-02-02
JPS6311625B2 (fr) 1988-03-15
DK296177A (fr) 1979-01-02
FR2396296A1 (fr) 1979-01-26
GB2000591A (en) 1979-01-10
BR7804212A (pt) 1979-04-10
DK139597C (fr) 1979-08-27
FR2396296B1 (fr) 1984-02-17

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